Ionescu-Shiley pericardial xenografts: follow-up of up to 6 years

The results of valve replacement with the Ionescu-Shiley pericardial xenograft compare favorably with results obtained with other bioprostheses. From March, 1977, to July, 1983, 497 Ionescu-Shiley pericardial valves were implanted in 463 patients at the University of Ottawa Heart Institute. There were 292 patients who had aortic valve replacement (AVR), 140 with mitral valve replacement (MVR), 28 with double valve replacement, and 3 with triple valve replacement. The survivors were followed regularly. Actuarial analysis of late results indicates an expected survival of 71% at 6 years for patients who underwent AVR and 72% at 3 years for patients who had MVR. The only valve-related deaths were due to endocarditis, which occurred at a rate of 3.9% per patient-year for aortic valves and 0.6% per patient-year for mitral valves. Despite a low usage of formal anticoagulation, embolic complications occurred at a rate of 1.4% per patient-year for aortic valves and 4.0% per patient-year for mitral valves. Five valves were removed for intrinsic failure after 36 to 72 months of follow-up. New York Heart Association Functional Class improved an average of 1.28 classes per patient.     

Late incidence and determinants of reoperation in patients with prosthetic heart valves.

OBJECTIVES: Reoperation is a relatively common event in patients with prosthetic heart valves, but its actual occurrence can vary widely from one patient to another. With a focus on bioprosthetic valves, this study examines risk factors for reoperation in a large patient cohort. METHODS: Patients (N=3233) who underwent a total of 3633 operations for aortic (AVR) or mitral valve replacement (MVR) between 1970 and 2002 were prospectively followed (total 21,179 patient-years; mean 6.6+/-5.0 years; maximum 32.4 years). The incidence of prosthetic valve reoperation and the impact of patient- and valve-related variables were determined with actual and actuarial methods. RESULTS: Fifteen-year actual freedom from all-cause reoperation was 94.1% for aortic mechanical valves, 61.4% for aortic bioprosthetic valves, 94.8% for mitral mechanical valves, and 63.3% for mitral bioprosthetic valves. In both aortic and mitral positions, current bioprosthesis models had significantly better durability than discontinued bioprostheses (15-year reoperation odds-ratio 0.11+/-0.04; P<0.01 for aortic, and 0.42+/-0.14; P=0.009 for mitral). Current bioprostheses were significantly more durable in the aortic position than in the mitral position (14.3+/-6.8% more freedom from 15-year reoperation; (P=0.018)). Older age was protective, but smoking was an independent risk factor for reoperation after bioprosthetic AVR and MVR (hazard ratio for smoking 2.58 and 1.78, respectively). In patients with aortic bioprostheses, persistent left ventricular hypertrophy at follow-up and smaller prosthesis size predicted an increased incidence of reoperation, while this was not observed in patients with mitral bioprostheses. CONCLUSIONS: These analyses indicate that current bioprostheses have significantly better durability than discontinued bioprostheses, reveal a detrimental impact for smoking after AVR and MVR, and indicate an increased reoperation risk in patients with a small aortic bioprosthesis or with persistent left ventricular hypertrophy after AVR.     

Clinical experience with omniscience and omnicarbon prosthetic heart valves

Omniscience valves were implanted in sixty-two patients. Twenty-eight of these patients underwent aortic valve replacement (AVR), 15 had mitral valve replacement (MVR) and 8 had aortic and mitral valve replacement (DVR). Post-operative events occurred in nine (5.9%/patient year) of the AVR group, in three (1.7%/patient year) of the MVR group and in three (5.4%/patient year) of the DVR group. The actuarial freedom from all events at five years in the AVR, MVR and DVR was 74 +/- 8%, 88 +/- 6%, 67 +/- 16%, respectively. Cardiac death occurred in four (2.5%/patient year) of the AVR, one (0.6%/patient year) of the MVR and two (3.6%/patient year) of the DVR. The freedom at five years in the AVR, MVR and DVR was 88 +/- 6%, 96 +/- 4%, and 77 +/- 14%, respectively. Valve-related complications were noted in four patients. Post-operative cerebral hemorrhage was seen in three of the AVR. Maximum opening angle of the Omniscience valve was 39.1 +/- 4.5 degrees at the aortic position and 44.6 +/- 9.7 degrees at the mitral position. Omnicarbon valves implanted in ninety-five patients, fifty-eight of these patients underwent AVR, 24 had MVR and 13 had DVR. Events occurred post-operatively in four (2.6%/patient year) of the AVR group, in three (12.2%/patient year) of the MVR group, but in none of the DVR group. The freedom at five years was 89 +/- 6% in the AVR and 84 +/- 8% at three years in the MVR. Post-operative cardiac death occurred in one (0.7%/patient year) of the AVR and in two (8.1%/patient year) of the MVR.(ABSTRACT TRUNCATED AT 250 WORDS)     

Long-term clinical results after combined aortic and mitral valve replacement

The results after 282 consecutive double (aortic & mitral) valve replacements (DVR) are compared with our previously reported experience after mitral (MVR, n = 810) and aortic valve replacement (AVR, n = 1753). All but one patient received Bj?rk-Shiley valves. The follow-up which closed on August 1, 1985 was 99.3% and covered 16,869 patient-years (mean 6.3 years/patient). Autopsies were performed in 74% of all fatalities. Early mortality rates were identical in the three patient groups, and late mortality did not differ between MVR and DVR patients. The fraction of valve-related mortality was similar in all groups. Anticoagulant-related bleeding was equally common in all patient groups. The incidences of thromboembolism, reoperation and valve failure did not differ between MVR and DVR patients, but were significantly higher than among AVR patients. With the exception of a slightly increased incidence of prosthetic valve endocarditis, the results after DVR equal those after MVR. In cases with severe mitral valve disease but borderline aortic valve disease, primary DVR is clearly justified and eliminates the need for, and risks of, a secondary AVR.     

Long-term Results in 1375 Patients Undergoing Valve Replacement with the Starr-Edwards Cloth-covered Steel Ball Prosthesis

The two principal considerations with prosthetic valves are durability and thromboembolism. With the widespread interest in recently developed prosthetic valves (porcine, tilting disc, Cooley), the long-term results at one institution with a single prosthesis were considered of particular importance. Accordingly, a 97% follow-up has been completed on 1375 patients (pts) undergoing prosthetic valve replacement with the Starr-Edwards cloth-covered steel ball prosthesis at New York University between October 1967 and December 1975. Operative procedures were as follows: aortic valve replacement (AVR): 470 pts; mitral valve replacement (MVR): 362 pts; combined AVR and MVR: 129 pts; other combined procedures: 414 pts. Overall operative deaths were 13.7%, 9% for AVR, 10.8% for MVR, and 18.6% for combined AVR and MVR. At seven years, AVR survival was 64%, and MVR survival 64.5%. There has been widespread pessimism, usually without significant data, about the cloth-covered prosthesis, because of concern of cloth wear, hemolysis and other complications. Therefore, a particularly significant finding by actuarial analysis was that 85% of surviving patients with isolated AVR remained free of emboli for five years. In pts surviving isolated MVR, 80% remained free of emboli for five years. Of those having embolic episodes, 33% were not on anticoagulants. Fatal hemorrhage from anticoagulants occurred in 0.8% of pts. Endocarditis occurred in 5.7% of the entire group, with 1.3% requiring reoperation. Clinically significant hemolysis occurred in 5.1% of the group, with only 0.2% requiring reoperation. Hence, the total frequency of clinically significant cloth-wear was less than 0.5%. These data indicate both the reliability and the limitations of the Starr-Edwards cloth-covered steel ball valve and can be used in comparing experiences with the more recently developed prostheses.     

Long-term outcomes of valve replacement with modern prostheses in young adults.

OBJECTIVES: To examine the multiple impacts of valve replacement on the lives of young adults. METHODS: Patients (N=500) between age 18 and 50 who had aortic valve replacement (AVR) and/or mitral valve replacement (MVR) with contemporary prostheses were followed annually. Events, functional status, and quality of life were examined with regression models. RESULTS: Median follow-up was 7.1+/-5.3 years (maximum 26.7 years). Five, 10, and 15-year survival was 92.7+/-1.7, 88.3+/-2.4 and 80.1+/-4.7% after AVR, and 93.1+/-2.3, 79.5+/-4.3 and 71.5+/-5.4% after MVR, respectively. Survival decreased with concomitant coronary disease (hazard ratio (HR): 4.5) and preoperative LV grade (HR: 2.0/grade increase) in AVR patients, and with atrial fibrillation (HR: 5.5), coronary disease (HR: 5.7), preoperative left atrial diameter (HR: 3.0/cm increase) and NYHA class (HR: 2.1/class increase) in MVR patients. Despite reoperation, late survival was equivalent between bioprostheses and mechanical valves in both implant positions. The ten-year cumulative incidence of embolic stroke was 6.3+/-2.4% for mechanical AVR patients, 6.4+/-2.9% for bioprosthetic AVR patients, 12.7+/-3.9% for mechanical MVR patients, and 3.1+/-3.1% for bioprosthetic MVR patients. Atrial fibrillation (HR: 2.8) and smoking (HR: 4.0) were risk factors for stroke in MVR patients. In AVR patients, SF-12 physical scores, freedom from recurrent heart failure, and freedom from disability were significantly higher in bioprosthetic than mechanical valve patients. Career or income limitations were more often subjectively linked to a mechanical prosthesis in both implant positions. CONCLUSIONS: Late outcomes of modern prosthetic valves in young adults remain suboptimal. Bioprostheses deserve consideration in the aortic position, as mechanical valves are associated with lower physical capacity, a higher prevalence of disability, and poorer disease perception. Early surgical referral and atrial fibrillation surgery may improve survival after MVR.     

Long-term experience with porcine aortic valve xenografts

Between 1971 and 1975, glutaraldehyde-preserved porcine aortic valve xenografts were employed for isolated replacement of the mitral valve (MVR) in 243 patients, replacement of the aortic valve (AVR) in 167 patients, and double valve replacement (AVR and MVR) in 51 patients. Postoperatively, long-term anticoagulation was not routinely given. Operative mortality rates for AVR, MVR, and double valve groups were 7.8, 6.0, and 11.8 per cent, respectively; the majority of early postoperative deaths were associated with concomitant coronary artery disease. No death was attributable to xenograft dysfunction. Follow-up of all patients was obtained. The total duration of follow-up for the MVR group was 347 patient-years, for the AVR GROUP 148 148 patient-years, and for double valve replacement 37 patient-years; maximum follow-up for these three groups was 4.4, 4.0, and 2.4 years, respectively. Actuarial analysis of postoperative survival rates at a common interval of 3 years showed 78 per cent for MVR patients, 91 per cent for AVR patients, and 80 per cent (projected) for patients with double valve replacement (85, 96, and 91 per cent for operative survivors, respectively. At this same interval 92 per cent of MVR patients, 99 per cent of AVR patients, and 93 per cent (projected) of patients with double valve replacement were free of thromboembolic episodes. Altogether, 12 of the total 512 valves implanted exhibited some evidence of dysfunction during the entire period of follow-up evaluation, but in only 2 instances (both mitral) was intrinsic pathological involvement of the xenograft tissue documented. Actuarial analysis of xenograft dysfunction at a common interval of 3 years after operation showed 95 per cent of MVR patients, 98 per cent of AVR patients, and 97 per cent (projected) of patients with double valve replacement to be free of this complication. These data support the use of glutaraldehyde-preserved porcine xenografts as superior bioprostheses that pose a low risk of thromboembolism without anticoagulation. The over-all durability of such valves, within the restriction of a maximum current follow-up interval of 4.4 years, appears comparable to that of currently available mechanical prostheses and justifies continued clinical use.     

Porcine cardiac bioprostheses: evaluation of long-term results in 990 patients

Clinical results with porcine bioprostheses were reviewed for 990 patients who underwent heart valve replacement from January, 1974, to December, 1980. Eight hundred and seventy-four Hancock, 283 Carpentier-Edwards, and 10 Liotta bioprostheses were used. In 23 patients, 26 mechanical prostheses were implanted as well. Overall operative mortality was 60 out of 990 (6.06%): 30 out of 506 (5.9%) for mitral valve replacement (MVR), 13 out of 287 (4.5%) for aortic valve replacement (AVR), 1 out of 4 (25%) for tricuspid valve replacement, 0 out of 2 for pulmonary valve replacement, and 16 out of 191 (8.4%) for multiple valve replacement. Cumulative follow-up covered 1,793 patient-years. (Actuarial survival at 7 years was 76.6 +/- 3% for MVR. At 6 years, it was 83.2 +/- 2.8% for AVR and 55 +/- 13.5% for multiple valve replacement.) Prosthesis-related survival at 7 years was 91.7 +/- 1.9% for MVR, and at 6 years, it was 96.6 +/- 1.5% for AVR and 95.1 +/- 2.2% for multiple valve replacement. Bioprosthesis survival, considering deaths or complications that led to reoperation as final events, was 84.2 +/- 3.7% at 7 years for mitral valves and 87.7 +/- 3.8% at 6 years for aortic valves. Emboli per 100 patient-years numbered 3.2 for MVR, 0.5 for AVR, and 1.6 for multiple valve replacement. Twenty-seven patients underwent reoperation, 12 for perivalvular leak, 5 for endocarditis, 6 for valve thrombosis, and 4 for primary tissue failure (linearized rates of 0.7, 0.3, 0.3, and 0.2% per patient-year, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)     

Durability and low thrombogenicity of the St. Jude Medical valve at 5-year follow-up

Between November, 1978, and December, 1983, 736 patients had valve replacement with the St. Jude Medical valve prosthesis. There were 478 patients with aortic valve replacement (AVR), 188 with mitral valve replacement (MVR), 63 with double valve replacement, and 7 with tricuspid valve replacement (they were not included in this study). The mean age at the time of operation was 46.7 years for patients having AVR and 48.6 years for those having MVR and AVR + MVR. Follow-up totaled 1,116 patient-years (range, 4 to 82 months). Early (30-day) mortality was lowest for isolated MVR (2.3%) and AVR (3.7%), and increased with reoperation or when associated procedures were combined with valve replacement. Patients undergoing reoperation or having associated procedures made up 49% of the AVR and 54% of the MVR groups. All patients were advised of the need for long-term anticoagulation with warfarin sodium. Nine patients (7 with AVR, 1 with MVR, 1 with AVR + MVR) had suspected or confirmed episodes of systemic thromboembolism, a linearized incidence of 0.99% per patient-year for AVR, 0.36% per patient-year for MVR, and 0.98% per patient-year for AVR + MVR. Eight patients with AVR underwent reoperation for prosthetic valve endocarditis (5 of the 8 patients had endocarditis prior to initial valve replacement). There were no instances of structural valve failure. There were 37 late deaths. Actuarial survival at 5 years (excluding early mortality, 95% confidence limits) was 89.8% for AVR, 84.8% for MVR, and 95.2% for AVR + MVR.(ABSTRACT TRUNCATED AT 250 WORDS)     

Paraprosthetic leak: a complication of cardiac valve replacement

Paraprosthetic leak (PPL) is a rare but potentially serious complication of cardiac valve replacement. Between 1974 and 1988, 1175 prosthetic valves were implanted in 1026 patients by one cardiac surgeon at St. Thomas' Hospital, London. Of these 539 (52.5%) were aortic (AVR), 334 (32.6%) mitral (MVR), 7 (0.7%) tricuspid, and 144 (14%) AV and MV double valve replacements (DVR). There were only 2 triple valve replacements. The prosthetic valves implanted were the Starr-Edwards (7%), Bjork Shiley (11.8%), Lillehei-Kaster (23%), Carpentier-Edwards bioprosthesis (35.2%), Duromedics bileaflet (16.4%) and a variety of other mechanical and bioprosthetic valves (6.6%). Over the 15 year period there were a total of 82 (7%) valve failures of which PPL was diagnosed in 29 (2.5%) valves in 24 patients. Presenting features included cardiac decompensation in 72%, bacterial endocarditis in 12% and haemolytic anaemia in 12%. One patient (4%) had no symptoms. Nineteen patients underwent re-operation. Median time to re-operation was 15 months (range 1-65 months) with a re-operative mortality of 22%. Clinical evidence of prosthetic valve infection was found in 79% of MVR and 67% of AVR. A heavily calcified aortic annulus, found in 47% of patients, may also have contributed to PPL after AVR.     

The initial experience with the ATS Medical mechanical cardiac valve prosthesis

BACKGROUND: From May 1994 through October 2000, a total of 1,146 patients underwent valve replacement with the ATS Medical mechanical cardiac valve prosthesis under a study protocol approved by international ethics committees (non-United States participants) or under a United States Food and Drug Administration-approved Investigational Device Exemption study. The study took place at 19 domestic and three international centers. METHODS: As required by the Food and Drug Administration's Heart Valve Guidance Document, only isolated implants were included in the study (double-valve implants were excluded), with operative and follow-up data collected from each center. RESULTS: Aortic valve replacement (AVR) was conducted in 801 patients (309 with coronary bypass) and mitral valve replacement (MVR) in 345 patients (78 with coronary bypass). Overall operative (< or = 30 days post implant) mortality was 2.1% (17 AVR = 2.1%, 7 MVR = 2.0%), 7 of which (AVR = 4, MVR = 3) were valve related. In 2,086 patient-years (1,459 AVR patient-years, 627 MVR patient-years) of follow-up, there were an additional 50 patient deaths of these, 18 were valve related, 9 due to anticoagulant related bleeding, 5 sudden/unexplained, and 1 each after stroke, thrombosis, prosthetic valve endocarditis, and thromboembolism. Late (>30 days post implant) valve-related complications included: transient and chronic thromboembolism (27 AVR (linearized rate 1.85%/patient-year) and 20 MVR (3.19%/patient-year), of which 11/47 (0.53%/patient-year) had chronic deficits, thrombosis (1 AVR = 0.07%/patient-year and 4 MVR = 0.64%/patient-year), paravalvular leak (10 AVR = 0.69%/patient-year and 8 MVR = 1.28%/patient-year), anticoagulant related hemorrhage (34 AVR = 2.33%/patient-year and 8 MVR = 1.28%/patient-year), prosthetic valve endocarditis (3 AVR = 0.21%/patient-year and 2 MVR = 0.32%/patient-year), and structural valve failure or dysfunction (0%). Echocardiographic gradients were proportional to valve size and did not significantly change over the follow-up period. CONCLUSIONS: This study documented the ATS Medical mechanical cardiac valve prosthesis to be a valuable addition to the surgeon's armamentarium in the treatment of cardiac valvular disease.     

Eight year experience with the CarboMedics bileaflet valvular prosthesis.

Two hundred and two patients (97 female and 105 male; mean age: 45. 5+/-9 years) received CarboMedics bileaflet valves during a period of eight years. Ninety-one patients received mitral, 72 aortic and 39 aortic+mitral valve prosthesis. Tricuspid plasty and coronary artery bypass surgery were the concomitant operations in 17 and 12 patients, respectively. The mean follow-up period was 24.7 months and the ratio was 91%. Overall operative mortality was 3.96% (8 patients); 2.78% for aortic valve replacement (AVR), 3.29% for mitral valve replacement (MVR) and 7.7% for double valve replacement (DVR). The late mortality rate was 2.89% for AVR, 2.2% for MVR and 8. 3% for DVR. The main cause of mortality was low cardiac output. The overall survival rate was 91.5% in 2 years. The actuarial freedom from thromboembolism in 2 years was 97% for AVR, 95% for MVR and 84% for DVR. No mortality due to heamorrhagic events was observed. CarboMedics prosthetic heart valves may be used satisfactorily with a low incidence of valve-related morbidity and mortality.     

Single-center experience with the bicarbon bileaflet prosthetic heart valve in Japan

We analyzed midterm results using the Bicarbon valve in a single center. Forty-four patients had aortic valve replacement (AVR), 48 had mitral valve replacement (MVR), and 13 had both aortic and mitral valve replacement (DVR). The mean age of the 105 patients was 61.2 +/- 11.3 years. The mean follow-up was 1.8 +/- 1.1 years with a cumulative follow-up of 188 patient-years. There were 5 early deaths (4.7%: 4 in the AVR group and 1 in the MVR group) and 5 late deaths (2.7% per patient-year: 3 malignancy, 1 cerebral hemorrhage, 1 myocardial infarction). Survival at 3 years was 91 +/- 4% in the AVR group, 92 +/- 5% in the MVR group, and 66 +/- 23% in the DVR group. The linearized incidence of thromboembolic complications, hemorrhagic complications, and paravalvular leaks in all patients was 1.06 +/- 2.34%, 1.60 +/- 2.53%, and 0.53 +/- 2.22% per patient-year, respectively. No other complications were observed. In conclusion, the Bicarbon prosthetic heart valve has shown excellent clinical results associated with a low incidence of valve-related complications.     

Early Results of Valve Replacement with the Björk-Shiley Convexoconcave Prosthesis

The Björk-Shiley convexoconcave prosthetic valve has design characteristics that may result in a lower incidence of thromboembolic complications than the conventional spherical Björk-Shiley prosthesis. We evaluated the results of valve replacement with the convexoconcave prosthesis in 248 patients receiving 301 prosthetic valves between March, 1979, and June, 1981. One hundred thirteen patients had aortic valve replacement (AVR), 73 had mitral valve replacement (MVR), and 62 had multiple valve replacement. Two hundred nine (84%) were in New York Heart Association Class III or IV. The median duration of follow-up was 13 months, and follow-up information was available for 246 (99%) of the patients. The actuarial incidence of freedom from thromboembolism at two years was 98% in the AVR group, 97% in the MVR group, and 87% in the group having multiple valve replacement. There were no documented episodes of valve thrombosis or mechanical failure and no fatal thromboembolic complications. The absence of valve thrombosis is in marked contrast to the results reported with the spherical disc valve. Although longer follow-up is necessary, it appears that the convexoconcave design represents a major improvement in the Björk-Shiley prosthesis.     

Long-term clinical results after aortic valve replacement with mechanical heart valves and mitral valve replacement with porcine valves]

Long-term clinical results of aortic valve replacement (AVR) with mechanical heart valves and mitral valve replacement (MVR) with porcine valves were analysed. Sixty-three patients received isolated AVR and 48 received isolated MVR. Sixty-eight patients with MVR including double or triple valve replacement were also added in order to evaluate the primary tissue failure (PTF). The patients with operative deaths were excluded. Survival rate at 11 years in AVR was 68 +/- 10% and 67 +/- 15% in MVR without statistical difference. At 11 years, 76 +/- 8% of the patients in AVR were free from valve-related complications in contrast with the poor result of 34 +/- 31% in MVR (p less than 0.01). Main cause of this poor result in MVR was PTF as indicated in following event free rates; 83 +/- 9% at 7 years, 61 +/- 25% at 10 years and 49 +/- 31% at 13 years. There was no statistical difference between patients of above 50 years and below 49 years in PTF. Valve-related death event free was 93 +/- 5% in AVR and 86 +/- 11% in MVR at 11 years (not significant), however, there was statistical difference in re-operation event free rate as 94 +/- 5% in AVR and 76 +/- 11% in MVR at 11 years (p less than 0.001). These results suggest that the use of porcine valves in mitral position is confined to the selected patients.     

Early clinical experience with the On-X prosthetic heart valve

The study aimed to assess the performance of the On-X valve (Medical Carbon Research Institute, Austin, TX). Between December 2000 and January 2003 On-X valves were implanted in 400 patients aged 19-85 years (mean: 55.6+/-16), 290 males and 210 females. There were 120 cases of aortic valve replacement (AVR), 258 mitral valve replacement (MVR) and 22 combined aortic and mitral valve replacement (DVR). Additional procedures were performed in 144 patients. Patients were followed up prospectively at 3- to 6-month intervals. Mean follow-up was 38.4+/-11.8 months (maximum 55.6 months). Overall hospital mortality was 3.5%. Freedom from adverse events at 4 years in the study were as follows: thromboembolism, 99.1% for AVR, 98.3% for MVR and 94.7% for DVR patients; thrombosis, 100% for AVR, 99.2% for MVR and 94.7% for DVR; bleeding events, 99.1% for AVR, 99.2% for MVR and 88.8% for DVR; prosthetic endocarditis, 98.2% for AVR, 99.2% for MVR and 94.7% for DVR. Overall survival at 4 years was 92+/-1%. At echocardiographical examination within 1 year of the AVR, the mean aortic valve gradient was 12.8+/-6, 10.3+/-3, 9.0+/-4, 8.3+/-3, and 6.2+/-3 mmHg for 19, 21, 23, 25, 27/29 mm valve sizes, respectively. MVR mean gradient was 4.9+/-2, 4.5+/-1.2 and 4.0+/-0.8 mmHg for 25, 27/29, 31/33 mm valve sizes, respectively. On-X valve is a highly effective mechanical valve substitute with low morbidity and mortality and good functional results.     

Mechanical versus bioprosthetic valve replacement in middle-aged patients.

OBJECTIVE: The current trend towards decreasing the age for selection of a tissue over a mechanical prosthesis has led to a dilemma for patients aged 50-65 years. This cohort study examines the long-term outcomes of mechanical versus bioprosthetic valves in middle-aged patients. METHODS: Patients (N = 659) aged between 50 and 65 years who had first-time aortic valve replacement (AVR) and/or mitral valve replacement (MVR) with contemporary prostheses were followed prospectively after surgery. The total follow-up was 3,402 patient-years (mean 5.1 +/- 4.1 years; maximum 18.3 years). Outcomes were examined with multivariate actuarial methods. A composite outcome of major adverse prosthesis-related events (MAPE) was defined as the occurrence of reoperation, endocarditis, major bleeding, or thromboembolism. RESULTS: Ten-year survival was 73.2 +/- 4.2% after mechanical AVR, 75.1 +/- 12.6% after bioprosthetic AVR, 74.1 +/- 4.6% after mechanical MVR, and 77.9 +/- 7.4% after bioprosthetic MVR (P=NS). Ten-year reoperation rates were 35.4% and 21.3% with aortic and mitral bioprostheses, respectively. Major bleeding occurred more often following mechanical MVR (hazard ratio [HR]: 3.3; 95% confidence interval [CI] 1.2, 9.0; P = 0.022), and the incidence of any thromboembolic event was more common after mechanical MVR (HR: 4.7; CI 1.4, 13.3; P = 0.01). Overall freedom from MAPE at 10 years was 70.2 +/- 4.1% for mechanical AVR patients, 41.0+/-30.3% for bioprosthetic AVR patients, 53.3 +/- 8.8% for mechanical MVR patients, and 61.2 +/- 9.2% for bioprosthetic MVR patients. Although a trend existed towards more MAPE amongst middle-age patients with tissue valves, multivariate analysis did not identify the presence of a bioprosthesis as an independent risk factor for MAPE (HR: 1.3; CI 0.9, 2.0; P = 0.22). CONCLUSIONS: In middle-aged patients, MAPE may occur more often in patients with bioprosthetic valves, but definitive conclusions necessitate the accumulation of additional follow-up. At present, these data do not support lowering the usual cutoff for implantation of a tissue valve below the age of 65.     

Preliminary Clinical Experience with the Jyros Bileaflet Mechanical Prosthesis

The Jyros bileaflet mechanical prosthesis is unique among bileaflet valve designs in that there is no fixed hinge mechanism and after implantation, the leaflets are free to rotate as determined by blood flow through the orifice. Between November 1992 and April 1994, 56 Jyros valves were implanted in 44 patients at 45 operations. There were 31 males and 13 females (ratio 2.3:1), with a mean age of 3714 and a range owelve patientsplacement (AVR) (26.7%), 19 had mitral valve replacement (MVR) (42.2%), and 14 had AVR plus MVR (DVR) (31.1%). In three DVR patients the Jyros valve was implanted only in the mitral position. There was one hospital death following DVR (2.3% mortality). Total follow-up of 341 patient-months (28.4 patient-years) is 100% complete. There were no late deaths. There was one reoperation for acute mitral prosthetic thrombosis (3.5%/patient-year). Another Jyros valve was inserted; leaving 53 valves at risk in 42 patients at the close of follow-up. There were no episodes of thromboembolism, transient ischemic attacks, endocarditis, hemolysis, or valve dysfunction, but three patients had four episodes of anticoagulant-related hemorrhage. Echocardiographic follow-up data was available in 29 patients and indicated satisfactory hemodynamic performance. Our early results with this unique prosthesis have been excellent; however, more extensive use and far longer follow-up are required to determine whether the theoretical advantages offered by the innovative design are manifest in lower complication rates than for other conventional bileaflet prostheses in current use.     

Experience with the Carpentier-Edwards Porcine Valve Prosthesis in 700 Patients

The Carpentier-Edwards porcine valve prosthesis has afforded our patients a satisfactory quality of life and a low incidence of valve-related complications at follow-up periods of up to five years. From December, 1975 to March, 1980, 768 prostheses were implanted in 700 patients (aortic valve replacement [AVR], 334; mitral valve replacement [MVR], 292; tricuspid valve replacement [TVR], 6; and multiple valve replacement, 68). One hundred and thirty-seven patients (19.6%) had had previous cardiac operations. Concomitant aortocoronary bypass was performed in 127 patients (18.1%). There were 52 hospital deaths, for a mortality of 7.4% (AVR, 4.8%; MVR, 9.2%; multiple valve replacement, 11.8%). Total follow-up was 1,047 patient-years (range, 6 to 60 months, mean, 19.4 months). There were 33 late deaths (AVR, 1.7% per patient-year; MVR, 4.0% per patient-year; multiple valve replacement, 8.1% per patient-year). Eight percent of AVR patients and 47% of MVR and multiple valve replacement patients were taking anticoagulants. The valve-related complications (expressed as events per 100 patient-years) were as follows: (1) thromboembolism (AVR, 0.94; MVR, 1.42; multiple valve replacement, 4.62); (2) infective endocarditis (AVR, 0.94; MVR, 0.24; multiple valve replacement, 2.31); (3) periprosthetic leak (AVR, 0.94; MVR, 0.71; multiple valve replacement, 3.46); and (4) valve dysfunction (MVR, 0.24). The only case of valve dysfunction was a calcified mitral prosthesis in a 13-year-old girl. Actuarial survival, including operative deaths, was as follows: AVR, 90.5% at 36 months; MVR, 84% at 36 months; and multiple valve replacement, 74% at 24 months. Of surviving patients, 93.6% were in New York Heart Association Class I or II at follow-up evaluation.     

Hematological complications with the St. Jude valve and reduced-dose Coumadin

We examined hematological complications in 415 patients having valve replacement with the St. Jude mechanical prosthesis (212, aortic valve replacement [AVR]; 159, mitral valve replacement [MVR]; and 44, AVR + MVR). There were 164 men and 251 women with a mean age of 59 years (range, 20 to 88 years). Preoperatively 386 patients were in New York Heart Association functional classes III and IV. There were 154 associated procedures (37%), the most common being myocardial revascularization. Overall hospital mortality was 7.5% (31/415), 7% after AVR, 8% after MVR, and 7% after AVR + MVR. All operative survivors were anticoagulated with Coumadin (crystalline warfarin sodium) to maintain the prothrombin time at 1.5 times control. During a mean follow-up of 21 months (range, 6 to 60 months), there were 29 late deaths (7.6%) and 5 patients (1.3%) lost to follow-up. No patient experienced structural valve degeneration. At 48 months, actuarial freedom from thromboembolism was 87% +/- 3% after AVR and 91% +/- 9% after MVR; from anticoagulation-related hemorrhage, 97% +/- 3% after AVR and 91% +/- 3% after MVR; and from hemolysis, 100% after AVR and 98% +/- 2% after MVR. Freedom from all valve-related morbidity at 4 years was 82% +/- 5% after AVR and 75% +/- 10% after MVR. Actuarial survival at 48 months was 80% +/- 4% after AVR and 65% +/- 7% after MVR.